Shining a Light on Solar Power: Q&A with Marc Grossman ’07

Marc Grossman '07, who graduated from the Haverford/Caltech 3/2 program, discusses his experiences working with eSolar, a solar thermal plant that uses an innovative software program to control renewable energy-producing fields of mirrors.

Since graduating from the Caltech 3/2 Program, which admits students from a select group of colleges into Caltech’s two-year engineering program after they have completed three years at their home institutions, Marc Grossman ’07 has been working as a project engineer with eSolar, an innovative new solar thermal plant based in Pasadena, California. Here he discusses his experiences with the Haverford Physics department and the challenges and rewards of working in a cutting-edge industry.

Haverford College:What’s exciting about working in the solar power industry today?

Marc Grossman: Solar energy has been around a long time, but for the first time ever we may be able to make it cost-competitive with fossil fuels, hydroelectric and nuclear power. We're moving at an incredible rate toward those goals, and if we do get to that cost-competitiveness, the market is wide open.

HC:What is cool and unique about eSolar?

MG:eSolar is particularly fast paced. I'm one year out of college and I've developed our mirror cleaning system. This isn't the type of large responsibility a new employee could expect to receive at a Boeing or a Lockheed-Martin. We're a very young crowd by any standard with a good half of our engineers probably less than 3 years out of college. As such, much responsibility is placed on relatively new engineers and so far that trust has paid off.

HC:Does eSolar use any particularly innovative technologies compared to other solar power plants?

MG:The incredible thing about eSolar's approach to delivering cost-competitive solar power is the software. We've figured out a way to build relatively inexpensive heliostats and to make them work as if they were much more expensive ones via software.

HC:How does that work?

MG:Our solar fields are composed of thousands of bathroom-size mirrors. These mirrors are mounted to a drive mechanism, which is computer controlled to reflect the incident energy upon the mirrors to our boiler [often called a receiver in the solar industry]. The mirror and drive assembly is called a heliostat. Past forays into concentrated solar thermal power have used very large heliostats, about the size of half tennis courts. These were made of many smaller mirror facets, that each needed to be adjusted for focus. These heliostats were incredibly large and required heavy machinery for installation. Then they each needed to be calibrated individually. This was an expensive and time consuming process, and therefore it was not deemed practical to use many smaller heliostats as we have done.

The trick is that we've completely automated the calibration process. It is entirely computer controlled. This has allowed us to use small heliostats, which has in turn allowed us to get cost advantages due to economics of scale.

HC:Did you enter Haverford knowing you wanted to become an engineer?

MG:No. I had no idea what I wanted to do. I did physics in the end because I liked it in high school and, quite frankly, because the physics professors were pretty incredible. Once I got a ways down the road in physics and I realized how theoretical it was I decided that it probably wasn't for me. It turns out that I was much more hands on than I had realized going into college, and fortunately for me I just stumbled into the [Caltech] 3/2 program.